Not necessarily. The first infection can be entirely asymptomatic, with the first known symptoms being mild like you describe. Still, a simple red bump -- which did not start as a blister and does not become one -- is unlikely to be herpes. But beyond that speculation, the only way to know is to be professionally evaluated.
Hi Doc
Thanks for the prompt response
One follow-up question, since I've read/heard that of the people who do show symptoms of herpes, the first outbreak is usually the worst, and if you are correct in saying this may be a recurrent outbreak, wouldn't I have displayed even more obvious symptoms before?
Welcome to the STD forum.
With a single "red bump", which presumably is not painful since you don't say so, I doubt this is herpes. If more bumps appear, if they evolve into blisters and then into open sores, I would be more concerned. In the event it actually is herpes, it is most likely a recurrent outbreak -- i.e. that you have been infected for some time; it is unlikely this is a new infection from the most recent encounter.
If the lesion persists, if other bumps/blisters appear, or if the same thing happens again someday, see a health professional for evaluation. Your local health department STD clinic would be an excellent choice for highly expert, confidential evaluation. If direct exam suggests herpes, you could have an HSV blood test to know with more certainty. But in the meantime, herpes doesn't seem likely.
Regards-- HHH, MD